Self-locking pulley.



PATENTED JUNE 2, 1,903. P. W. SMITH.

SELF LOOKING PULLEY.

APPLIOATIQN FILEDMAY 24, 1902.

N0 MODEL.

z. 0 VIII?! T1 Witnesses Inknl'or,

FREDERICK W.sMITH,-

Patented June 2, 1903.

PATENT ()FFICE.

OF CLEVELAND, OHIO.

SELF-LOCKING PULLEY.

SPECIFICATION forming part of Letters Patent No. 729,968, dated'J'une 2,1903.

Application filed May 24, 1902.

To all whom it may concern:

Be it known that I, FREDERICK W. SMITH, a citizen of the United Statesof America, and aresident of Cleveland, in the county of Guyahoga andState of Ohio, have invented certain new and useful Improvements inSelf-Lockin g Pulleys, of which the following is a specification.

This invention relates to self-locking pulleys; and it consists in anadditional improvement on the pulley patented on October 13, 1891, andnumbered 461,316. The object of this improvement is to provide a meansfor easily and quickly releasing the grip on the hoisting-rope; and itconsists in combining a trip-lever with the rock-frame having adequatepower to release the grip on the hoisting-rope. It is found inlarge-sized pulleys lifting heavy loads that the grip becomes so tightlylocked that force is required for releasing thegrip in order to enablethe, load to be lowered. This is what my improvement is designed toaccomplish.

In the accompanying drawings, Figure 1 is a side elevation of theself-locking pulley having my improvement attached; Fig. 2 is a sideelevation of the pulley with the side plate removed,showin g thelocking-grip open. Fig. 3 is a like side elevation showing the gripshut.

A is a pulley-frame consisting of two side: plates A A, joinedtogether-by bolts or rivets a a.

B is a rock-frame consisting of two side plates B B, and said rock-frameis fulorumed in the frame A at (Z. In said pulley-frame A are providedtwo sheaves O D,and in the lower part of the rock-frame B is a sheave E.The journal of sheave 0 passes through a slot 1) in the sides of therock-frame B to allow of a little movement of said rock-frame forgrip-Serial No. 108,876. (No model.)

ping the rope. The rope R is secured at e in the end of pulley-frame Aand passes down to the pulley-block G, thence up and over the sheave E,thence down again and through block G, then back up again over sheaves CD, thence down for hauling, as indicated by the arrows. In the frame 13'is provided a segmental gripping-block F, whichis used to bear on therope for grippingthe same when required for locking the pulleys andpreventing the load'from pulling down.

The numerals 1 2 3 455 andthe arrows indicate the run and direction therope takes in hauling up. I

I is a lever fulorumed on the side of the frame A below sheave D, havingits short end connected by a link J to the journal of sheave F. To thelong end of said lever I is attached a rope or cord K, by means of whichthe lever ispulled upon to release the grip when the grip is too tightlylocked for easy unlocking. Having described my invention, what I claimis- In a self-locking pulley, the combination with the pulley-frame Aand the rock-frame ranged to operate substantially as and for thepurpose specified.

Signed by me at day of May, 1902.

- FREDERICK -W. SMIT-I-I. Witnesses:

GEO. W. TIBBITTS, EDWARD F. SPURNEY.--

Cleveland Ohio, this 23a-

